As seen above, Wednesday morning the writer tweeted that he's left the series, despite his first issue (#19) not scheduled for release until next month. The news comes as DC Comics is currently promoting the start of his and artist Tony S. Daniel's run in an extended preview (as seen here) in current New 52 titles.
Diggle has been solicited as the writer of issues #19-21 (April-June).
In subsequent tweets, Diggle added:
“It was the toughest decision I’ve ever had to make, especially with Superman’s 75th anniversary and Man of Steel on the horizon."

“But it was the right decision. No regrets. Onwards!"

“Sincere thanks to Matt Idelson for inviting me to follow Grant Morrison on Action Comics. I hope we still get to work together someday.”

In response, DC's Executive Direction of Publicity Alex Segura posted this tweet a short time after announcing Daniel would be taking over as writer of the series:
<blockquote class="twitter-tweet">Regarding ACTION COMICS - artist Tony Daniel will be expanding his role and taking over as writer and artist for the remainder of the arc.&mdash; Alex Segura (@alex_segura) <a href="https://twitter.com/alex_segura/status/314425197954494464">March 20, 2013</a></blockquote>

DC declined to comment or provide any further details.
In the wake of Diggle's news, several creators have tweeted at him, seemingly commiserating with whatever prompted the writer to depart the title so quickly.
Writer/artist Rob Liefeld, who left DC and all New 52 work in high-profile fashion because of what he alleged to be extensive editorial interference in his storytelling, tweeted: "Sheesh," to which Diggle responded: "That's what I said!" Liefeld's response: "Been there. Was very much looking forward to your run."
Liefeld's response of "been there" was echoed by another writer who left work at DC, Nick Spencer, who wrote "sorry to hear that, man. Been there. You made the right call."
Added Mark Waid via tweet: "Apparently, what happens in Charlotte stays in Charlotte--including promises to freelancers. Condolences, but best of luck!"
Waid was likely referring to DC's editorial-creator summit held in Charlotte, NC last month.
Look for more information as it becomes available.Developing...
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